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Python Exception Handling

• Common error types: SyntaxError, NameError, TypeError, FileNotFoundError, IndentationError.

• SyntaxError: violates Python syntax rules, e.g., while True without colon.

• NameError: uses undefined variable, e.g., print(new_variable).

• TypeError: unsupported operation between types, e.g., 1+'a'.

• FileNotFoundError: attempts to open non-existent file.

• IndentationError: improper code block indentation.

• Error message structure: Traceback (error roadmap), File (location), Line (line number), ErrorType, and details.

• Basic exception handling: try: (risky code) + except ErrorType: (handler).

• Catch specific errors: except ZeroDivisionError:, except FileNotFoundError:.

• Catch-all errors: except Exception as e: stores error details in e.

• Provide user-friendly messages in except blocks to help users understand mistakes.

• Multiple except blocks handle different errors; only the first matching block executes.

• Tuple-style catching: except (Error1, Error2): handles multiple errors together.

• else clause: runs only when try block succeeds, separates success logic.

• finally block: always executes, used for cleanup like closing files.

• Manual exception raising: raise ValueError("message") for validation.

• Resource management pattern: try → except → else → finally.